Anytime children or adolescents play sports or exercise in hot weather, they're at risk of heat-related illnesses. Understand how heat-related problems happen and what steps you can take to prevent them.

Your child might be vulnerable to dehydration and other heat-related illnesses in a hot or humid environment if he or she:

Is sick or had a recent illness, especially involving diarrhea, vomiting or a fever

Is taking certain supplements or medications, such as cold medicine

Has had a previous heat-related illness

Has a chronic condition, such as diabetes

Isn't well-rested

Heat-related problems are most likely within the first few days of practice in a hot environment. That's why it's best to take it easy at first, gradually increasing the amount of activity — and the amount of protective equipment — as the days pass. Young athletes might need up to two weeks to safely acclimate to the heat.

During hot and humid conditions, coaches are encouraged to:

Require young athletes to drink plenty of fluids before practice and during regular beverage breaks — even if they aren't thirsty

Make sure clothing is light colored, lightweight and loosefitting, or exposes as much of the skin as possible

Decrease or stop practices or competitions if necessary, or move them indoors or to a shady area

To determine when heat and humidity make strenuous exercise risky for young athletes, your child's coach might monitor the wet-bulb globe temperature (WBGT) — the standard index of temperature and humidity combined. If the WBGT is too high, outdoor athletic activities might need to be limited or canceled.

Even mild dehydration can affect your child's athletic performance and make him or her lethargic and irritable. Left untreated, dehydration increases the risk of other heat-related illnesses, including heat cramps, heat exhaustion and heatstroke.

Encourage your child to pay attention to early signs and symptoms of dehydration, including:

Dry or sticky mouth

Thirst

Headache

Dizziness

Cramps

Excessive fatigue

Remind your child that he or she should report signs and symptoms to the coach right away. Don't let embarrassment keep your child on the field. If dehydration is detected early, fluids and rest might be all that's needed. If your child seems confused or loses consciousness, seek emergency care.

If your child plays sports in hot weather, encourage him or her to drink plenty of fluids before, during and after practices and games. Teach your child the signs and symptoms of dehydration, as well as the importance of speaking up if they occur.

Involve your child's coach, too. Talk to the coach about adjusting the intensity of practice depending on the temperature and humidity on the field — and support the coach's decision to cancel games and practices when it's dangerously hot outside.

References

Parents' and coaches' guide to dehydration and other heat illnesses in children. National Athletic Trainers' Association. http://www.nata.org/health-issues/heat-illness. Accessed July 9, 2014.

Centers for Disease Control and Prevention, et al. Heat illness among high school athletes — United States, 2005-2009. MMWR. 2010;59:1009. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5932a1.htm. Accessed July 9, 2014.

American Academy of Pediatrics, et al. Climactic heat stress and exercising children and adolescents. http://pediatrics.aappublications.org/site/aappolicy/index.xhtml. Accessed July 9, 2014.

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